Added JS Sorting Algorithms

JAVASCRIPT/Algorithms/insertionSort.js

@@ -0,0 +1,13 @@
+const insertionSort = (arr) => {
+  for (let i = 1; i < arr.length; i++) {
+    let currentValue = arr[i];
+    let j;
+    for (j = i - 1; j >= 0 && arr[j] > currentValue; j--) {
+      arr[j + 1] = arr[j];
+    }
+    arr[j + 1] = currentValue;
+  }
+  return arr;
+};
+
+// console.log(insertionSort([45, 3, 79, 14, 459, 21, 999])); // Output: [3, 14, 21, 45, 79, 459, 999];

JAVASCRIPT/Algorithms/mergeSort.js

@@ -0,0 +1,17 @@
+function mergeArrays(leftArr, rightArr) {
+  let array = [];
+  while (leftArr.length && rightArr.length) {
+    if (leftArr[0] < rightArr[0]) array.push(leftArr.shift());
+    else array.push(rightArr.shift());
+  }
+  return [...array, ...leftArr, ...rightArr];
+}
+
+function mergeSort(arr) {
+  const middle = arr.length / 2;
+  if (arr.length < 2) return arr;
+  const leftArr = arr.splice(0, middle);
+  return mergeArrays(mergeSort(leftArr), mergeSort(arr));
+}
+
+// console.log(mergeSort([45, 3, 79, 14, 459, 21, 999])); // Output: [3, 14, 21, 45, 79, 459, 999];

JAVASCRIPT/Algorithms/pallindrome.js

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+const checkPallindrome = (value) => {
+  const len = value.length;
+
+  for (let i = 0; i < len / 2; i++) {
+    if (value[i] !== value[len - 1 - i]) {
+      return false;
+    }
+  }
+  return true;
+};
+
+const checkPallindrome2 = (value) => {
+  const data = typeof value === "number" ? value.toString() : value;
+  return data === data.toString().split("").reverse().join("");
+};
+
+// console.log(checkPallindrome(456789313987654)); // Output: true
+// console.log(checkPallindrome2(456789313987654)); // Output: true
+// console.log(checkPallindrome("456789313987654")); // Output: true
+// console.log(checkPallindrome2("456789313987654")); // Output: true

JAVASCRIPT/Algorithms/quickSort.js

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+const quickSort = (arr) => {
+  if (arr.length <= 1) return arr;
+
+  let pivot = arr[0],
+    leftArr = [],
+    rightArr = [];
+
+  for (var i = 1; i < arr.length; i++) {
+    arr[i] < pivot ? leftArr.push(arr[i]) : rightArr.push(arr[i]);
+  }
+
+  return quickSort(leftArr).concat(pivot, quickSort(rightArr));
+};
+
+console.log(quickSort([45, 3, 79, 14, 459, 21, 999])); // Output: [3, 14, 21, 45, 79, 459, 999];

JAVASCRIPT/Algorithms/selectionSort.js

@@ -0,0 +1,16 @@
+const selectionSort = (arr) => {
+  const len = arr.length;
+
+  for (let i = 0; i < len; i++) {
+    let min = i;
+    for (let j = i + 1; j < len; j++) {
+      if (arr[j] < arr[min]) min = j;
+    }
+    if (min != i) {
+      [arr[i], arr[min]] = [arr[min], arr[i]];
+    }
+  }
+  return arr;
+};
+
+// console.log(selectionSort([45, 3, 79, 14, 459, 21, 999])); // Output: [3, 14, 21, 45, 79, 459, 999];